Spent Fuel Casks 101 — What We Regulate and Why

Mark Lombard
Director, Division of Spent Fuel Management

CASK_101finalWe talked back in March about dry casks for storing spent nuclear fuel and how they work. Today we want to introduce you to the different things the NRC looks at each time we review a cask application.

To recap: spent fuel is placed into cooling pools at reactor sites when it can no longer efficiently sustain a nuclear reaction. Dry casks give utilities an alternate way to store their spent fuel, freeing up space in the pools. They were first developed back in the 1980s because space in the pools – designed for temporary storage – was growing short.

Our requirements for dry cask storage can be found in 10 CFR Part 72. All structures, systems and components important to safety must meet quality standards for design, fabrication and testing. And they must be structurally able to withstand wind, rain, snow and ice, temperature extremes, hurricanes and tornadoes, earthquakes, and fires and explosions.

Fuel pellets, rods, and casks_r9Part 72 and related NRC guidance on casks and storage facilities also detail specific engineering requirements. Casks must be designed to keep water out so the fuel can’t have a chain reaction, as it would in a reactor. The casks must also shield workers and the public from radiation. They must safely remove the heat remaining in the spent fuel. And the materials used in dry casks and their physical properties must be well-understood and analyzed.

The NRC has dozens of experts in different scientific and engineering disciplines whose job is to review cask applications (which can be hundreds of pages long) and the detailed technical designs they contain. We will explain in more detail in later blog posts what our experts look for and how they go about approving a cask design.

Moving Forward on Updating Cost vs. Benefit Analysis

Alysia Bone
Rulemaking Project Manager
 

 What are the costs and benefits of the NRCs’ safety regulations? It’s a question we regularly ask as one way to make sure our regulations make sense.

We’re in the process of updating two cost-benefit guidance documents — NUREG/BR 0058 and NUREG/BR 0184 – at the direction of the Commission and after receiving public input. Our update plan is now available online. Our goal is to make sure we are using the right tools to compare costs and benefits so we implement changes that reduce risks and enhance safety in a responsible way.

The updated guidance will do a number of new things. It will include the cost for replacing the energy generated by nuclear power plants. It will also improve the method for putting a dollar amount on health impacts from radiation. We’ll revise terms and definitions for consistency across the agency, and we’ll look at how we use more subjective factors in cost-benefit assessments. We expect these changes will bring our cost-benefit process up to date and help us make more consistent decisions for reactors as well as other licensed activities.

NRC staff experts have been working on this in response to the Commission’s direction for a paper on our approach to considering the economic consequences of a potential nuclear accident. The Commission was responding to the staff’s August 2012 paper and recommendations, which were based on a review of the agency’s economic consequences process in place at the time of the 2011 Fukushima accident. The 2012 staff paper described where considerations of economic consequences fit in the NRC’s review of new reactor licenses, renewal of existing licenses, or major changes to our safety regulations. That earlier paper recommended updating the cost-benefit guidance used to perform these analyses.

In the plan to update cost-benefit guidance, we’ve committed to presenting any identified potential policy issues to the Commission for its consideration. As the staff further develops these potential policy issues, staff will hold public meetings to receive feedback from industry and members of the public, before advising the Commission.

Starting a Reactor Design Review the Right Way

Scott Burnell
Public Affairs Officer
 

A few months ago, Korea Hydro and Nuclear Power Co. gave the NRC an application to certify the company’s Advanced Power Reactor 1400 design for use in the U.S. We’d been having “pre-application” discussions with the company since April 2010.

In September of this year, the company felt its information was ready for a full review. After our acceptance check of the application, however, we’ve decided the process should remain at the pre-application stage.

While most of the application’s sections and chapters have enough information for the NRC to review, there are important exceptions. For example, our technical experts don’t see a clear path for predictably and efficiently reviewing important areas such as instruments and controls, how human actions affect reactor operations, and assessing risk.

We also didn’t see enough detail for some specific technical issues, such as reactor coolant pump design, potential corrosion of some internal reactor parts and protecting plant staff from radiation. Other areas referenced technical reports to be submitted in the future.

At this point it’s the company’s decision on how to proceed – if they wish to continue pre-application meetings and related discussions, we’ll certainly do so. The formal review, however, will have to wait until the NRC is satisfied the application has enough information for our staff to create a reasonable, reliable schedule and milestones for the certification process.

Let’s be clear – none of this represents any sort of NRC technical conclusion regarding the Korean reactor design. We’re well aware that other countries are building or considering the design, and we continue to work with a multinational group discussing this and other new reactor designs. This decision doesn’t set any precedents, either. We’ve previously decided against accepting the initial applications for both a U.S.-based design certification and a new reactor operating license. The NRC also followed this path for a couple of applications to renew existing U.S. reactor licenses.

The bottom line is that the NRC must ensure proposed reactor designs can meet our safety requirements. We owe it not only to the public to do that job properly, but also to applicants to do so effectively and predictably. The best way to do that is to have the appropriate information in hand before we begin our work.